The presently disclosed subject matter relates to an electrode pad having an adhesive gel layer, and particularly to an electrode pad in which noises caused by chest compression or the like can be reduced.
In order to perform rescue from a cardiac arrest state due to ventricular fibrillation (VF), recently, not only public facilities but also offices, convenience stores, and the like are equipped with an AED (Automatic External Defibrillator). An AED is used for, when ventricular fibrillation or the like occurs, applying a strong defibrillation shock (electric shock) to the heart to eliminate a cramp in the heart muscle.
On the other hand, cardiopulmonary resuscitation (CPR) is known as a method of maintaining a chance of rescuing a person who seems to stop breathing and have no cardiac activity. According to 2010 AHA (American Heart Association) Guidelines and JRC (Japan Resuscitation Council) Guidelines 2010 which show a procedure of performing CPR, it is recommended to perform chest compression in advance of defibrillation with an AED.
In a rescue procedure in which the lifesaving rate becomes lower as time elapses, it is preferable that the period required for automatic electrocardiogram analysis performed by an AED is as short as possible. When chest compression is performed in advance of defibrillation with an AED, however, noises caused by chest compression affect the automatic electrocardiogram analysis, so that the analysis is hardly performed. Therefore, chest compression is interrupted until the automatic electrocardiogram analysis performed by an AED is completed.
An electrode pad is known in which, in order to check as soon as possible the effect of defibrillation applied to a patient in ventricular fibrillation, a strong acid gel is used in the electrode pad as means for reducing a high DC offset voltage generated on the electrode pad (see U.S. Pat. No. 6,845,272).
As an electrode pad which has a low DC offset voltage and a low impedance, and in which the S/N ratio is high, an electrode pad having a soft conductive electrode configured by Sn, and a gel containing tin salts is known (see U.S. Pat. No. 4,674,512).
In the electrode pad which is disclosed in U.S. Pat. No. 6,845,272, and in which a strong acid gel is used as a gel, in order to assure a long storage period, however, a metal layer in an electrode must be thick in consideration of corrosion due to oxidation of the electrode. When the metal layer is thick, the flexibility of the electrode pad is lowered, and the contacting property with respect to the skin is impaired. In a worse condition, there may arise a problem in that the skin is burned during defibrillation. In the case of an electrode pad using a strong acid gel, the skin irritation is so high that inflammation may occur. In order to prevent this from occurring, a double-layer gel structure in which a weak acid gel is formed on the side of the skin is employed.
Moreover, the electrode pad which is disclosed in U.S. Pat. No. 4,674,512 cannot provide an electrocardiogram waveform which enables automatic electrocardiogram analysis to be performed during cardiopulmonary resuscitation by chest compression.